The Paris Agreement, which aims to ensure average global temperature does not rise by more than 2C above pre-industrial levels, was originally signed by Barack Obama in 2015 who said it would open the floodgates for a new era of energy efficiency and low carbon power.

However, the current President of the US, the world’s second largest polluter, has called climate change a “hoax” and questioned the role of carbon dioxide in global warming.

Since initial media reports suggesting President Trump was to pull the US out of the agreement, he tweeted that he had not yet made up his mind.

If the US does withdraw, it will join Syria and Nicaragua in not being part of the pact. Russia has signed the deal but not ratified it.